Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6763e7fe334ee2b…

MALICIOUS

PDF

85.5 KB Created: 2021-06-25 20:26:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: e19233cd04ef14fb5c70f6c2486632dd SHA-1: 71c564006e2862bf4b996c65d8956a848bb867d4 SHA-256: b6763e7fe334ee2b301d3e5c2515acc767b3796e300c6f07889e0673335cac68
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm hosted on compromised CMS uploads, pointing to numerous PDF files on various domains. While no scripts were extracted, the presence of multiple links to potentially malicious PDFs suggests a phishing or redirection attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/0daa459f9b4cc19d416b28e6f717e629/dejojaso.pdf In PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160987402acaec---38749678417.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16076608c6bb98---67713830676.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/nafasegubepulubigike.pdfIn PDF document text
    • https://paklya.su/design/img/upload/file/felefajiwizukejuzu.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b3d4c39e49---43201988742.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/retenovukofomusamazawari.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097c1e340272---mitutuvumubitakewibube.pdfIn PDF document text
    • http://davcpundri.com/css/file/27487698292.pdfIn PDF document text
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/e7bc668fa6fa522beebe5fd2de4adccd/18013539713.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c2898ed8e7c---bonidegubadupezijilajudar.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/1253303bedadf3979458a813f8a442b4/sepamabanijenuvexe.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/bgid58tl242s06op6clrkocim7/wegujezuza.pdfIn PDF document text
    • http://hutbephottaihaiphong24h.com/upload/files/kufuvisubuxa.pdfIn PDF document text
    • https://www.colours-of.com/wp-content/plugins/super-forms/uploads/php/files/o24t94slc77vem06d2e2ggh5f8/80639621264.pdfIn PDF document text
    • http://clasesholandes.com/userfiles/file/nukexijukiderenu.pdfIn PDF document text
    • http://webelievedin1984.com/clients/6/67/676624d6593aa512bfa6e10e765af00e/File/17322895448.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a2c7755053---wuvabajifupemobotivivebu.pdfIn PDF document text
    • http://ffarchitettura.it/userfiles/files/32229154605.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091d6aed3c8d---noxozevika.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608362914adae---94321255672.pdfIn PDF document text
    • http://textingrights.com/userfiles/files/nomikevojularup.pdfIn PDF document text
    • https://harkakotony.hu/UserFiles/file/82858016347.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c325118b10---bibem.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/2021530542403075.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/kokukibimaduwaragimunifes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=wuthering+heights+online+subtitratPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8D2 17968 bytes
SHA-256: 1c909f7feb3e62c840908bf3e64614c7463cdbb88d62bf4360dfee6086f274a4
font_01_sfnt_off0001164a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1164A 10620 bytes
SHA-256: e3d8f9416f093eaaea0c271fd7f90e94697e54a2900b117b63de814b11adbb01
font_02_sfnt_off00012e8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E8C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1